how do I adjust the play in the steering system on 1993 Chevrolet Suburban 2500

There is too much play in the steering & there is a groaning sound when I make turns.

Your steering box should have four bolts on top; this is a Type 800 Steering gear. Also on top is a 'lock screw',; nut must be loosened to tighten up slop in steering gear. Ideal/desirable steering gear play is less than one inch (left to right total while moving steering wheel back and forth). Occasionally check before tighting the lock nut.